We shall continue our studies along three lines: (1) An identification of the nicotinic chemoreceptors in sympathetic ganglion cells by the use of x-bungarotoxin and by immunological studies. (2) The muscarinic excitatory synaptic potentials in sympathetic ganglion cells will be explored, in particular the ionic mechanisms which are responsible for these slow potentials. (3) In sympathetic ganglia one obtains on nerve stimulation synaptic potentials which last for five to ten minutes. We plan to continue attempts to identify the transmitter that produces these synaptic events.